中国西部钻孔应变仪台网工作回顾与前瞻
|
摘要
中国西部钻孔应变仪观测台网始建于上世纪 80 年代末期,采用的 RZB-1 型电容式钻孔应变仪具有 10-10量级的应变灵敏度和小于 10-7/a 的飘移。9 台仪器分别安装在新疆、甘肃与四川的乌什、西昌和武都等台站,以观测因构造活动引起的地壳应变能的积累,并研究相关的地震前兆特征。总结了台网建设与观测工作,及其用于对台站附近发生的强震的监测预报结果。其中,4 种类型的震前异常应变变化较为明显:(1) 应变固体潮畸变与年周变畸变;(2) 幅度达 10-6 应变的积累,并伴随压、张性跳变;(3) 异常应变积累持续时间达数月;(4) 测得的主应力方向震前向震中方向偏转。最后,对发展我国井下观测技术提出了 3 点建议。
The West China Borehole Strainmeter Networks are established in the late eighties of the twentieth century. RZB-1 borehole strainmeter with strain sensitivity of 10-10 and strain drift less than 10-7/year were adopted to detect the crustal strain energy built-up from active tectonic processes in order to study earthquake precursors. Strainmeters were installed in 9 observatories in three provinces of west China,Xinjiang,Gansu and Sichuan,and are kept on operating up to the present. This paper summarizes the observation data of strainmeters and their application to monitoring and predicting strong earthquakes occurring round the station. Four kinds of abnormal strain changes before big earthquakes are evident,that is,(1) distortion of strain tides and annual variation form,(2) strain building up of amplitude as much as 10-6 with compressive and tensive jumps,(3) duration of abnormal strain accumulation lasting few months,and (4) axis of the major principal stress turning and pointing to epicentre before the coming shock. At last,three suggestions are brought forward to help developing borehole observation and retative research in China.
The West China Borehole Strainmeter Networks are established in the late eighties of the twentieth century. RZB-1 borehole strainmeter with strain sensitivity of 10-10 and strain drift less than 10-7/year were adopted to detect the crustal strain energy built-up from active tectonic processes in order to study earthquake precursors. Strainmeters were installed in 9 observatories in three provinces of west China,Xinjiang,Gansu and Sichuan,and are kept on operating up to the present. This paper summarizes the observation data of strainmeters and their application to monitoring and predicting strong earthquakes occurring round the station. Four kinds of abnormal strain changes before big earthquakes are evident,that is,(1) distortion of strain tides and annual variation form,(2) strain building up of amplitude as much as 10-6 with compressive and tensive jumps,(3) duration of abnormal strain accumulation lasting few months,and (4) axis of the major principal stress turning and pointing to epicentre before the coming shock. At last,three suggestions are brought forward to help developing borehole observation and retative research in China.
引文
1欧阳祖熙.RDB-1型电容式地应变计[A].见:第一届全国地应力会议论文选编[C].北京:地震出版社,1977,337～348
2欧阳祖熙,李秉元,贾维九等.一种钻井式地应力场测量系统[A].见赵国光.地壳构造与地壳应力文集(2)[C].北京:地震出版社,1988,11～20
3GladwinM T.High precision multi-component borehole deformation monitoring[J].Rev.Sci.Instrum.,1984,55:2011～2016
4杨志荣.1987年1月24日新疆乌什6.4级地震前兆异常及其预报[J].中国地震,1987,3(4):6～12
5蒋靖祥,赖爱京,胡群等.利用钻孔应变资料预报新疆伽师强震群[J].西北地震学报,1998,20(20):16～21
6蒋靖祥,尹光华,李川等.RZB-1型分量式钻孔应变与新疆及邻区强震[A].见:全国钻孔应力应变观测技术研讨会论文集[C].北京:地震出版社,2002,1～14
7张宗润,舒桂林.钻孔应变应力观测与地震预报研究[A].见:第三届全国地应力会议专集[C].北京:地震出版社,1994,274～280
8舒桂林,张宗润.RZB 型电容式钻孔应变仪的观测实践及地震预报效果综述[A].见赵国光.地壳构造与地壳应力文集(10)[C].北京:地震出版社,1997,22～29
9高原,蒲小武,陈彦平等.昆仑山口西8.1级地震与甘、川应变资料变化的关系[A].见:全国钻孔应力应变观测技术研讨会论文集[C].北京:地震出版社,2002,151～157
10尹亮,李兴坚,陈兰新等.昆仑山口西MS8.1地震前高台钻孔应变异常[J].大地测量与地球动力学,2002,22(4):89～91
11朱航.使用钻孔应变测值成功预测2001年10月27日云南永胜6.0地震的实践[A].见:全国钻孔应力应变观测技术研讨会论文集[C].北京:地震出版社,2002,140～146
2欧阳祖熙,李秉元,贾维九等.一种钻井式地应力场测量系统[A].见赵国光.地壳构造与地壳应力文集(2)[C].北京:地震出版社,1988,11～20
3GladwinM T.High precision multi-component borehole deformation monitoring[J].Rev.Sci.Instrum.,1984,55:2011～2016
4杨志荣.1987年1月24日新疆乌什6.4级地震前兆异常及其预报[J].中国地震,1987,3(4):6～12
5蒋靖祥,赖爱京,胡群等.利用钻孔应变资料预报新疆伽师强震群[J].西北地震学报,1998,20(20):16～21
6蒋靖祥,尹光华,李川等.RZB-1型分量式钻孔应变与新疆及邻区强震[A].见:全国钻孔应力应变观测技术研讨会论文集[C].北京:地震出版社,2002,1～14
7张宗润,舒桂林.钻孔应变应力观测与地震预报研究[A].见:第三届全国地应力会议专集[C].北京:地震出版社,1994,274～280
8舒桂林,张宗润.RZB 型电容式钻孔应变仪的观测实践及地震预报效果综述[A].见赵国光.地壳构造与地壳应力文集(10)[C].北京:地震出版社,1997,22～29
9高原,蒲小武,陈彦平等.昆仑山口西8.1级地震与甘、川应变资料变化的关系[A].见:全国钻孔应力应变观测技术研讨会论文集[C].北京:地震出版社,2002,151～157
10尹亮,李兴坚,陈兰新等.昆仑山口西MS8.1地震前高台钻孔应变异常[J].大地测量与地球动力学,2002,22(4):89～91
11朱航.使用钻孔应变测值成功预测2001年10月27日云南永胜6.0地震的实践[A].见:全国钻孔应力应变观测技术研讨会论文集[C].北京:地震出版社,2002,140～146
版权所有：© 2023 中国地质图书馆 中国地质调查局地学文献中心